President Biden and Democrats have ridden a wave of good news all summer — on an improving economy, big legislative wins, even unlikely gains by Ukraine.

Why it matters: Democrats spent the first half of the year looking for a way to break the momentum working against them. Now, they're praying they can keep their positive momentum — and GOP missteps — going with enough force to hold the Senate and maybe the House.

The big picture: Inflation's fury has been cooling. Gas prices are down. Democrats have enjoyed legislative successes, including passage of the Inflation Reduction Act.

• The Supreme Court's decision overturning the constitutional right to an abortion has energized Democratic voters, with women registering to vote at unusually high levels and Republicans losing their advantage in the generic ballot.

What we're watching: At the end of last week, Biden's team celebrated a small but significant breakthrough in their long-running effort to help Ukraine fight back against the Russian invasion.

• Elections are rarely driven by foreign policy, but compared with the political impact of last year's Afghanistan withdrawal, Ukraine showing new fight against Russia is welcome news to the administration.

Driving the news: The August Consumer Price Index (CPI) report, out today, will become the newest data point by which to measure their odds.

Between the lines: Republicans' self-inflicted troubles have helped Democrats as well.

• Donald Trump — perhaps Democrats' greatest voter-motivator — is again the center of repeated news cycles, giving Dems a powerful turnout machine.
• Senate Republican Leader Mitch McConnell and his allies have been privately bemoaning the quality of Trump-backed candidates in key Senate races. Sen. Rick Scott (R-Fla.), chairman of the Republican Senate's campaign arm, has botched his fundraising strategy and is in an open war with McConnell.
• Several Trump-endorsed candidates — especially Blake Masters in Arizona — are underperforming Republican expectations. The party's Senate campaign committee is low on funds after burning through cash in an unsuccessful attempt to recruit online donors.

Republican money troubles are compounded by Trump hoarding $100 million in his Save America PAC.

• McConnell has been indirectly urging Trump to spend this cash on vulnerable Republicans that he helped nominate — like Masters in Arizona — but so far, to McConnell's chagrin, Trump has kept the money largely to himself.
• Save America has devoted less than 5% of its nine-figure warchest to backing other Republican candidates, according to Federal Election Commission records.
• $2 million of that aid has gone toward taking out Republicans in key primary contests—Gov. Brian Kemp in Georgia (he prevailed anyway) and Rep. Liz Cheney in Wyoming (she lost).

Reality check: Despite the streak of discouraging news, Republicans still have a clear path to retaking the Senate majority. They only need to net one seat to win back the upper chamber, and there are plenty of paths to get there even if recruits fizzle out.

• In Georgia, public polling now shows Herschel Walker holding a narrow advantage over Sen. Raphael Warnock. With Gov. Brian Kemp on track for a victory over Democrat Stacey Abrams, Republicans are increasingly optimistic he can pull Walker over the finish line.
• In Wisconsin, Republicans are blitzing Democrat Mandela Barnes on crime, calling him a "dangerous Democrat." They predict Barnes' August lead over Sen. Ron Johnson (R-Wis.) will evaporate under sustained attacks.
• Concerns over Democrat John Fetterman's health are cutting into his advantage over Mehmet Oz in the Pennsylvania Senate race. Oz is questioning Fetterman's ability to serve and challenging him to debates. Five state Democratic Party officials "expressed worries about Fetterman's health and whether Republican attacks were swaying voters," according to Reuters.

The bottom line: If Republicans hang on in Wisconsin and hold the other Trump states, they'd need to win only two of the other six battleground races (Pennsylvania, Nevada, Georgia, New Hampshire, Arizona, Colorado).

• It's far from a guarantee, but it wouldn't take a red wave to accomplish, either.

Axios' Hans Nichols and Lachlan Markay contributed to this report.