Beto O'Rourke was the featured guest last week at a rally designed to unify Dallas County Democrats, but he had a more inclusive message to deliver.

While his local Democratic brothers and sisters were munching on red meat and talking about kicking GOP butt in November, O'Rourke was reaching out to the independent and Republican voters he'll need to beat incumbent Republican Ted Cruz for a Senate seat.

"I'm glad the Democratic Party is coming together, but unity has to extend beyond our own party," O'Rourke said last week in Dallas. "Not only are we not going to win if we can't get beyond just our own party, but we're not going to be able to deliver on the high expectations we're setting for people."

For O'Rourke, running for Senate in Texas is a delicate dance, one in which he has to fire up his Democratic base, but at the same time get Republicans to break with their party and support him.

The congressman from El Paso can't win without the backing of voters outside of his party. That's because Republicans enjoy a sizable advantage in the statewide electorate. Some progressive groups say they need at least 850,000 more voters just to turn the state purple.

A Democrat hasn't won statewide office since 1994. And the last Democrat to hold a Senate seat was Bob Krueger, who lost to Republican Kay Bailey Hutchison in 1993. Cruz won the seat after Hutchison retired when her term ended in 2012.

O'Rourke has thrilled Texas voters with his underdog campaign, one that will visit all 254 counties, including Republican strongholds. He's been to places like Fort Worth, Plano, Garland and Farmers Branch, looking for Republicans like his mother to support his candidacy.

Texas senator Ted Cruz speaks to a mourner during a vigil along Avenue M and Highway 6 following a shooting at Santa Fe High School. Ten people were killed and 10 others injured. Dimitrios Pagourtzis was booked into the Galveston County Jail on capital murder charges. (Andy Jacobsohn / Staff Photographer)

It won't be easy.

Texas Republicans are some of the most conservative voters in the country, and O'Rourke's policy proposals don't match their ideology. It also appears Cruz is solidifying his lead over O'Rourke, according to the most recent Quinnipiac Poll released Wednesday. The first poll in April showed a tight race, but Wednesday's results had Cruz with a 12 percentage point lead.

As Cruz points out, O'Rourke supports sanctuary cities, while Republican voters don't. He's pushing gun control policies that are not popular in Texas. He's out of step with Republican voters on issues related to immigration reform and border security.

O'Rourke would argue that he's appealing to voters by selling them on common sense ideas for the economy, immigration and health care, and that Texas' problems in those areas are too critical to accept what Cruz and Republicans are offering. But polls show most Republicans think more like Cruz on those issues.

At first glance, O'Rourke is fighting a losing battle, but one that will provide winning results for Democrats down the road because they are currently in rebuilding mode.

Some of Texas' leading Democrats, however, do see a path for 2018.

The national climate for Republicans is perilous because of President Donald Trump. Democrats, still smarting that the New York businessman beat Hillary Clinton for the White House, are better organized and more enthusiastic than in recent years.

Wendy Davis, the 2014 Democratic nominee for governor, summed up the party's statewide chances last Sunday on Lone Star Politics, a show produced by KXAS-TV (NBC 5) and The Dallas Morning News.

She said there is a climate where people are "champing at the bit" to vote against Trump and his policies. Davis added that Democratic candidates in congressional races, including the 32nd Congressional District in the Dallas area, will help drive voters to the polls for O'Rourke and Lupe Valdez, the Democratic nominee for governor.

In the 32nd congressional district, Democrat Colin Allred is challenging incumbent Republican Pete Sessions.

Cruz has conceded that Democrats are motivated and would "walk across glass" to vote in November, though he adds that there are more conservatives in Texas and if they show up, he wins.

For O'Rourke and other Democrats, turning out the Democratic base is more important than appealing to Republicans. The more new Democrats that show up at the polls means one less conservative O'Rourke has to recruit.

Texas is a state with a deep divide between Republicans and Democrats, so the candidate with the most productive base of support generally wins. There are few independents or crossover voters to make that much of a difference.

O'Rourke is saying the right things about appealing to Republicans and Democrats, but he needs an overwhelming turnout from his own party to upset Cruz.