(CNN) Beto O'Rourke is giving Ted Cruz a run for his money in the Texas Senate contest.

The Democratic underdog from El Paso outraised the first-term Republican senator and former presidential candidate by $1.5 million -- $2.3 million to $800,000 -- from the beginning of 2018 through mid-February. That impressive fundraising haul comes after O'Rourke also outpaced Cruz in the closing quarter of 2017, $2.4 million to $1.8 million.

Cruz still holds a clear advantage in the race. When it comes to cash on hand, Cruz leads O'Rourke by a little more than $1 million.

The Republican also has recent Texas electoral history on his side. Democrats haven't won a statewide election there since Bob Bullock's re-election as lieutenant governor in 1994. The last Democrat elected to the US Senate from Texas? Lloyd Bentsen in 1988.

For Democrats to have a chance at taking control of the Senate, they may have to make states like Texas competitive. Democrats -- or independents who caucus with them -- are defending 25 seats this year, while Republicans are defending just eight. The GOP has a 51-49 advantage at the moment.

Read More