President TrumpDonald John TrumpBill Kristol resurfaces video of Pence calling Obama executive action on immigration a 'profound mistake' ACLU says planned national emergency declaration is 'clear abuse of presidential power' O'Rourke says he'd 'absolutely' take down border wall near El Paso if he could MORE on Thursday night dismissed former President Obama's reemergence on the campaign trail ahead of the November midterm elections, arguing it could fire up his own base.

“By the way, he’s campaigning again. That’s good news. When I was running, I swear, I thought he campaigned harder than Hillary ClintonHillary Diane Rodham ClintonO’Rourke heading to Wisconsin amid 2020 speculation The Hill's 12:30 Report — Presented by Kidney Care Partners — Lawmakers scramble as shutdown deadline nears Exclusive: Biden almost certain to enter 2020 race MORE. And we won big,” Trump said at a rally in Las Vegas on Thursday evening.

ADVERTISEMENT

Obama burst back onto the scene earlier this month in a speech in Illinois that included blistering rebukes of Trump’s performance while in office on everything from his tax plan to his response to the deadly white nationalist rally in Charlottesville, Va., last year.

The former president also travelled to California to rally for several House candidates, including some running in Republican-held districts, and Ohio to campaign with Democratic gubernatorial candidate Richard CordrayRichard Adams CordrayOn The Money: Consumer bureau proposes scrapping borrower safeguards from payday loan rule | Negotiators running out of time to avert shutdown | Trump nominates World Bank critic as its next chief Consumer bureau proposes scrapping borrower safeguards from payday loan rule Supreme Court should do what Congress won’t: Rein in the Bureau of Consumer Financial Protection MORE.

Obama will also travel to Philadelphia on Friday to rally with Democratic Sen. Bob CaseyRobert (Bob) Patrick CaseyGOP wants to pit Ocasio-Cortez against Democrats in the Senate Biden speaking to Dems on Capitol Hill as 2020 speculation mounts: report GOP senators: Trump should not declare border emergency during State of the Union MORE and Gov. Tim Wolf (D).

Obama had previously avoided the campaign trail since leaving office, wary of nationalizing tight state races or rallying GOP voters in some areas.

Trump's comments came during a rally in Nevada on behalf of Sen. Dean HellerDean Arthur HellerTrump suggests Heller lost reelection bid because he was 'hostile' during 2016 presidential campaign Trump picks ex-oil lobbyist David Bernhardt for Interior secretary Oregon Dem top recipient of 2018 marijuana industry money, study finds MORE (R-Nev.), one of the most vulnerable Republicans running for reelection in November.