Democrat Beto O'Rourke will ride into San Antonio on yet another wave of record fundraising while incumbent Ted Cruz will take the stage for the final debate of the campaign for U.S. Senate cushioned by recent polls showing the Republican opening a widening lead.

Here are a few things to keep an eye out for once the debate begins at 8 p.m. Central time Tuesday:

No more Mr. Nice Guy?

When Cruz and O'Rourke squared off in Dallas last month, experts said the Republican scored by staying on message and staying on the offensive. O'Rourke, who when he began campaigning last year was still somewhat unknown outside his native El Paso, was considered the winner of the likability contest by pushing high ideals over pointed attacks.

But since that Sept. 21 event, polls have showed O'Rourke slipping from 3-5 percentage points behind Cruz to as much as 9 points down. So the question hanging in the air now is, will O'Rourke go negative.

And if he does, will the tactic be effective for a candidate who has been branding himself as a post-partisan politician who'd bring a unifying voice to the often fractious U.S. Senate?

Will Cruz coast?

Short answer: It's not in his nature. But there is the sense in the Cruz camp that the wind is at his back. Even when a biting attack piece not affiliated with O'Rourke surfaced last week questioning whether Cruz has the stones of a true Texan, his aides took a pass on the opportunity to counter-punch.

Cruz himself, however, seems always on the lookout for a chance to slam his rival. Remember that as the Dallas debate was winding down, the moderators asked each candidate to say something nice about the other.

O'Rourke complimented Cruz's family and said he understood the toll campaigning takes on a father of young kids. Cruz, sounding warm and sincere, couldn't resist saying that the nicest thing about O'Rourke was that he's very committed to the policies of socialism.

That suggests Cruz is unlikely to play it safe, even if it seems like he has a lead.

The sound of no one cheering

This was supposed to be the third of three Cruz-O'Rourke debates, but the middle one was scuttled when it appeared it would have conflicted with the Senate vote on the confirmation of now-Supreme Court Justice Brett Kavanaugh.

The canceled debate in Houston was to have been in a town-hall setting with audience members participating in the questioning, and presumably registering their approval or lack of same with each candidates' answers.

The debate in Dallas was in a theater on the campus of Southern Methodist University, and partisan in the audience routinely ignored instructions not to clap, yell or even whoop whenever their guy scored or the other guy stumbled.

San Antonio's event will be in the studio of TV station KENS 5. No audience, and therefore, no audience reactions.

The politics of personalities

Speaking of Kavanaugh, watch for the level of gusto Cruz delivers when he mentions his vote to confirm the controversial justice. If he goes all in and shrugs aside the allegations of sexual impropriety, Cruz will show that he and Senate Majority Leader Mitch McConnell are on the same page that the Supreme Court fight was a jolt of caffeine for the Republican base.

Conversely, if O'Rourke stokes the anger progressives brought to the confirmation fight, it will suggest he's betting Kavanaugh remains a motivator for moderates and Democrats, especially moderate and Democratic women.

The same goes for how they handle mentions of President Donald Trump, Washington Democrats Nancy Pelosi and Charles Schumer and perhaps even attorney and Trump nemesis Michael Avenatti, who recently endorsed O'Rourke via Twitter.

Cruz relishes lumping O'Rourke in with establishment Democrats. O'Rourke often says the fortunes of the Democratic establishment are not his problem.

The closing window of time

Finally, watch for both candidates to talk about the calendar. Six days after the debate — Oct. 22, to be exact — early voting starts. It ends Nov. 2. The actual Election Day is Nov. 6. Regardless of what other points are made on the stage Tuesday night, they won't matter one bit if voters forget those dates. Count on both candidates to not let you forget.

John C. Moritz covers Texas government and politics for the USA Today Network in Austin. Contact him at John.Moritz@caller.com and follow him on Twitter @JohnnieMo.