Beto O'Rourke, former Representative from Texas and 2020 Democratic presidential candidate, speaks during the American Federation of State, County & Municipal Employees (AFSCME) Public Service Forum in Las Vegas, Nevada, U.S., on Saturday, Aug. 3, 2019.

Jacob Kepler | Bloomberg | Getty Images

Beto O'Rourke wants you to know he's a presidential candidate.

The former Democratic congressman returned to his hometown of El Paso, Texas, nearly two weeks ago to comfort a community reeling from a shooting at a Walmart that left 22 people dead. Calls have grown for him not to leave the state — and abandon his flagging bid to challenge President Donald Trump in favor of a run against Sen. John Cornyn, R-Texas.

On Thursday, O'Rourke made it clear he has his eyes on nothing but the White House in 2020.

"I will not in any scenario run for the United States Senate. I'm running for president, I'm running for this country, I'm taking this fight directly to Donald Trump and that is what I'm exclusively focused on doing right now," O'Rourke told MSNBC on Thursday night.

O'Rourke put himself on the national map last year with a competitive challenge to Sen. Ted Cruz, R-Texas. But he has struggled to break into the top tier of the presidential race: he currently polls sixth in an average of national polls of the Democratic primary field. Some Texas Democrats and one of the state's largest newspapers have pushed O'Rourke to try to unseat Cornyn in a state turning a shade bluer.

Democrats have lost several top Senate recruits to the presidential contest as they try to break the GOP's 53-47 hold on the chamber. Control of the Senate will help to determine not only what parts of the next president's agenda will pass, but also who serves on federal courts for decades to come.

O'Rourke's decision to stay in the presidential race comes as Democrats criticize the GOP-held Senate for not taking up a House-passed universal gun background check bill meant to stem gun violence. After the shooting in El Paso and another massacre in Dayton, Ohio, only hours later, Democrats saw flipping control of the Senate as even more important as they try to pass gun restrictions.

On Thursday, O'Rourke downplayed the idea that he had the best chance to beat Cornyn in Texas, saying any one of at least seven Democrats running in the state's Senate primary would be a better lawmaker than Cornyn.

The former lawmaker is considered a strong candidate in no small part because of his fundraising prowess. He took in a staggering $79 million during his run against Cruz in last year's midterms. Contenders for the Democratic Senate nomination include M.J. Hegar, who lost a close House race to GOP Rep. John Carter last year, state Sen. Royce West and Houston City Council member Amanda Edwards.

O'Rourke's competitive race with Cruz — he lost by about 2.5 percentage points — and Democrats' two wins over House GOP incumbents last year have buoyed the party's hopes for more success in Texas in 2020. Three Republicans have recently retired from districts that could prove competitive in 2020.

Senate Democrats got one good piece of electoral news Thursday. Former Colorado Gov. John Hickenlooper dropped out of the presidential race and said he would give "serious thought" to challenging vulnerable GOP Sen. Cory Gardner next year.

O'Rourke used a speech in El Paso on Thursday to outline a new path for his campaign. The former congressman has called Trump a white supremacist, saying his alarmist rhetoric about immigrants helped to inspire the shooting targeting Latinos in El Paso.

Instead of joining his rivals to campaign in early voting states such as Iowa and New Hampshire, O'Rourke will instead travel to places affected by Trump's policies. He will start on Friday in Mississippi, where U.S. agents detained about 680 undocumented workers earlier this month.

On Friday morning, O'Rourke also released a new plan to combat white nationalism and gun violence.

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