Republicans put their massive war chest and newly all-digital operation to the test ahead of Tuesday's special elections.

The GOP, along with state parties, launched an all-out effort and came out on top by winning two congressional seats and providing what they see as a boost for the party and President Donald Trump’s campaign as the coronavirus pandemic continues to impact the road to November.

Former Navy pilot Mike Garcia captured Democrat Katie Hill's California seat while Republican state Sen. Tom Tiffany handily won in Wisconsin on Tuesday, giving two Trump-backed candidates wins as polling shows support for the president waning amid the coronavirus.

With in-person campaigning on hold and get-out-the-vote efforts relegated online, Republicans treated Tuesday’s special elections as a dry run for November after turning their operation fully digital in mid-March, hoping the wins provide a road map for campaigning in the fall.

The party, which has over $255 million in the bank along with the Trump campaign, invested over $2 million combined in both races in Wisconsin and California.

Republicans flexed their campaign muscle and bombarded voters with hundreds of thousands of mailers, ramped up phone banking efforts and made millions of calls to voters across the states, and held nearly 200 virtual meetings and trainings across the two states ahead of the elections, according to a senior Republican official.

Trump also personally pushed for the wins in both races on his Twitter feed, and instead of holding a rally ahead of the Wisconsin special election, which the president has made a habit of doing, he even appeared on a tele-townhall and urged voters in the district to vote for Tiffany the day before the election, the official said.

Amid the public health crisis, in-person voting is now largely seen as a secondary option to vote-by-mail, with state officials across the country urging voters to cast their ballots by mail in remaining primaries. Republicans, seeking to quickly adapt their tactics for the long run to ensure that voters are educated on the process, sent constant reminders to voters via phone and text about filling out and returning absentee and mail-in ballots in both districts.

The Republican National Committee’s embrace of vote-by-mail in these two elections appears at odds with President Trump’s disparaging rhetoric on the issue - but it does seem to reflect the party’s broader acknowledgement of the need for a robust operation to meet voters where they feel most safe to vote.

In the days leading up to Tuesday’s election, Trump repeatedly railed against California and claimed the election would be “rigged.” The president lashed out over the state adding an additional polling station in a heavily minority part of the district amid the coronavirus pandemic, claiming in a tweet without evidence that Democrats were “trying to steal the Mike Garcia Congressional Race.”

Trump celebrated the wins on Twitter, writing, before Smith conceded on Wednesday, “Big Congressional win in California for Mike Garcia, taking back a seat from the Democrats. This is the first time in many years that a California Dem seat has flipped back to a Republican. Also, Tom Tiffany beat his Democrat rival BIG in Wisconsin. Two great Congressional WINS!”

Republicans pull off win in suburban Los Angeles

In a district that covers, in part, the northern suburbs of Los Angeles, Republicans pulled off a significant win ahead of the fall, in a district that Hill won by 9 points two years ago and Hillary Clinton carried by seven points in the 2016 presidential election.

Currently, Garcia, a political newcomer, is leading Christy Smith, the Democratic state lawmaker seeking to succeed Hill, by double digits, 56% to 44%. Smith conceded to Garcia on Wednesday, acknowledging her current deficit but making clear she’s not done fighting for the seat ahead of a rematch in the fall.

Trump Victory, the joint effort between the Trump campaign and the Republican National Committee, invested nearly $1 million in the CA-25 special election, making 1.4 million get-out-the-vote (GOTV) voter contacts into, sending over 300,000 texts into CA-25, and holding dozens of virtual events geared at energizing supporters.

Republicans sent nearly 400,000 mailers to voters and utilized big-name surrogates like RNC Chairwoman Ronna McDainiel and Donald Trump Jr. to hold virtual trainings and events ahead of the election.

“These back-to-back special election victories are a testament to the enthusiasm and support voters have for President Trump and Republicans across the country. Our permanent, data-driven ground game is unmatched, and this momentum will carry us forward to victory in November,” RNC National Press Secretary Mandi Merritt said in a statement.

The highly-anticipated special election to replace Hill, who resigned last year after the House Ethics Committee opened an investigation over allegations she had inappropriate relations with a congressional staffer, which she denied, was expected to be competitive, with Democrats tempering expectations in the tight race for Smith.

"This is a really hard election runoff electorate," a Democratic strategist told ABC News before Tuesday’s election. "We were eyes wide open as to how tough of a road this was going to be."

In the weeks leading up to Tuesday, the race moved from "lean Democratic" to a "toss up," underscoring the outsize importance of the matchup. The contest drew national attention on both sides due to its timing and location in the middle of both the pandemic and the suburbs - a critical area of the country often seen as bellwethers for the general election.

Garcia’s win appears to tilt electoral fortunes back in the GOP’s favor, with Republicans casting the race as the end of the 2018 blue wave. A GOP strategist argued that Democrats’ momentum is “stifled” and the Republicans are seeing evidence of an energized and engaged electorate on par with 2016.

The strategist also contended that the president’s handling of the coronavirus crisis was “not a drag” on the GOP candidates in these races, but instead, showed “huge” turnout among Republicans.

Outside groups, too, echoed that sentiment, with David McIntosh, the president of the conservative outside group Club for Growth, which poured $1 million across both special elections, saying in a statement, "These election results show that in the midst of a global pandemic, this level of voter turnout shows pro-growth, pro-deregulation policies trounce the big-spending power-grabbing agenda put forward by Pelosi's Democrats."

But come November, when the candidates will likely be locked in another close matchup to secure a full term, a different electorate could lead to a different outcome.

"Even if Garcia were to narrowly win, Republicans wouldn't be able to count it as a firm step towards the majority, because he could easily lose a higher-turnout, guaranteed rematch against Smith in November," Dave Wasserman, the House Editor for The Cook Political Report, wrote before Tuesday.

"He is their unicorn," a Democratic strategist told ABC News of Garcia last week. "If you extrapolate anything from this race, it is that he's an outlier."

Battleground Wisconsin boost GOP’s hopes

Just one month after Democrats touted Jill Karofsky’s victory in the state Supreme Court race as an early sign of cracks in the "red" suburban wall in Wisconsin, Tiffany delivered a blow to Democrats in Tuesday’s special election in the 7th congressional district.

Tiffany defeated Tricia Zunker, a Democrat and law professor, by a 14-point margin - a smaller edge than Trump, who carried the district in 2016 by 20 points, and former GOP Congressman Sean Duffy, who vacated the seat last year due to family reasons after winning reelection by 22 points in 2018.

Trump Victory made a similar investment in Wisconsin to CA-25, the joint effort between the Trump campaign and RNC, dropping more than $1 million into the race and carrying out 2.4 million GOTV calls into WI-07 as part of the nearly 4.5 million voter contacts the team has made in Wisconsin this cycle alone, a party official said.

The team also sent more than 520,000 mailers and sent 60,000 texts into WI-07 on May 11 alone.

And while campaign events remain on hold, President Trump, who regularly descends into districts and holds massive rallies to boost Republican candidates ahead of special elections, made an appearance on a GOTV tele-townhall Monday evening for the Wisconsin race along with RNC chairwoman Ronna McDaniel. On Monday night, there was a Tiffany for Congress tele-townhall. Participants included Chairwoman McDaniel, Sean Duffy, Tom Tiffany, and President Trump.

The president spoke to an audience of all voters in WI-07, where he reiterated his support for Tiffany and thanked volunteers, urging them to vote, a Republican official said. Others on the call included Chairwoman McDaniel, former Republican congressman Sean Duffy and Tiffany.

Staffers on the ground in Wisconsin held over 80 virtual Trump Victory Leadership Initiative (TVLI) Trainings to train volunteers to back Tiffany, along with nearly 80 virtual MAGA Meet-Ups, which are informal get-togethers among Trump supporters.

Tiffany entered into Tuesday night the favorite to win, but Democrats are now seeking to spin Zunker’s loss ahead of November, arguing that the margin in the rural district that covers much of northwestern Wisconsin continues to show that “voters are running away from Trump.”

In a memo shortly after the race was called, the Wisconsin Democratic Party posited, “The ground continues to shift under Trump in rural Wisconsin. This shift has occurred as the suburbs outside of Milwaukee (WOW Counties) continue to move away from Republicans, and the Green Bay area, including Brown, Outagamie, and Winnebago counties (BOW) continue to move from deep purple to light blue.”

A shift in support, even a small one, could hurt Trump’s chances of once again capturing a state he narrowly won four years ago by only about 23,000 votes.

The Trump campaign took a victory lap in a statement to ABC News: "Tom Tiffany trounced his opponent by 15% in a seat Barack Obama once carried by 8% and Mike Garcia is well on his way to flipping a Democrat seat in California to Republican for the first time in 22 years," Trump campaign deputy communications director Ali Pardo said. "These victories made clear what we already knew, enthusiasm for President Trump has continued to grow and voters want four more years of strong Republican leadership, not a Green New Deal and socialist agenda that will permanently destroy our economy."

Special elections test vote-by-mail apparatus

With less than six months until the general election, Republicans might be adapting to the new reality on the fly, but in Wisconsin, they have had two test runs in the span of a month - before the state becomes the center of the battlefield for the presidency.

Since last month’s election in Wisconsin, the state GOP has been fine-tuning their efforts in the digital sphere to drive up early and mail voting.

“We added more digital and more phones to that effort,” Mark Jefferson, the executive director of the Wisconsin Republican Party told ABC News of the improvements the party made to their vote-by-mail campaign since the April 7 spring election. “We tracked the response rate a little bit closer this time around to make sure that our people were turning them in. We changed a mail piece around a little bit more so that people were a little more able to understand that they also needed to turn in a copy of their photo ID in order to get that ballot back.”

“There were still some people that weren't fully up to speed on that so we need to improve on that some more,” he conceded, before adding, “But we changed a little bit on how the mailings went out ... We changed a little bit of the digital message. So, we continue to get a pretty strong response.”

The push to mail voting by the state Republican party comes against the backdrop of Trump raising the specter of election fraud, which he often invokes without evidence.

But as state parties are grappling with campaigning without door knocking and with scaled-back in-person voting, the test runs are key to providing a roadmap for November.

“The longer we have to go into this world where we're just doing Zoom trainings and Zoom meetings and targeting people through the internet, the more important it is that your data be accurate,” Jefferson said. “And so, that gives us an advantage right there … to flip the switch” to a non-traditional campaign.

“This was a good tune up,” he said, looking ahead to the fall.