Washington (CNN) Democratic Rep. Beto O'Rourke raised more than $6.7 million in the first three months of 2018, his campaign announced Tuesday, a sign that the El Paso Democrat is poised to put up a significant fight against incumbent Republican Sen. Ted Cruz.

"BREAKING: We raised $6.7 million in the first 3 months of 2018. No PACs, no special interests. Just people. More than 141,000 grassroots contributions. Grateful to all of you," O'Rourke tweeted.

O'Rourke's fundraising haul is the largest of his campaign so far, surpassing the previous high of $2.4 million, raised in the last three months of 2017.

Democrats haven't held statewide office in Texas since 1994.

At the last Federal Election Commission reporting deadline -- before Texas held its primaries, covering the first 45 days of 2018 -- filings showed O'Rourke had outraised Cruz $2.3 million to $800,000.

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