PLANO, Texas (CBSDFW.COM) – Democratic Presidential candidate Beto O’Rourke’s call for a mandatory buy-back of assault style rifles is generating more than national headlines.

Late Friday afternoon, his Campaign Manager Jen O’Malley Dillon announced following O’Rourke’s performance in last week’s debate in Houston, they saw a surge in donations.

While he continues to poll well in Texas, that’s not the case in all-important Iowa or the three other early states of New Hampshire, Nevada and South Carolina.

At a campaign rally in Plano Sunday, O’Rourke, the former El Paso Congressman, repeated what he said several nights earlier at the Houston debate: He wants to ban the sale of assault-style rifles, such as AR-15s and AK-47s and force existing owners to sell them to the government.

Beto O’Rourke campaigns in Plano on Sunday (CBS 11)

The crowd responded by chanting “Hell yes,” the same line O’Rourke used during the debate.

Most Republicans reject that, and some Democrats have also shot down O’Rourke’s idea, including Senate Minority Leader Chuck Schumer, who told reporters this week he doesn’t “know of any other Democrat who agrees” with O’Rourke, “but it’s no excuse not to go forward.”

O’Rourke tweeted, “My response is: What has he been able to get done?”

At the rally in Plano, he criticized members of his own party as timid. “I’m a lifelong Democrat and for too long, Democrats have played defense.”

To gain momentum, experts say O’Rourke must go on offense.

He told the crowd, “I love being back in Texas” and reminded them during his Senate run against Republican Ted Cruz last year, he won more votes than any other Democrat in Texas.

“Texas has 38 electoral college votes. Imagine a Texan at the top of the ticket.”

A new Texas poll this week by UT Tyler shows O’Rourke in second place behind former Vice President Joe Biden.

Biden scored 26% with Democrats and 28% with Independents, while O’Rourke had 20% among Democrats and 19% among Independents.

Vermont Senator Bernie Sanders was close behind with 18% among Democrats and 17% among Independents.

But while O’Rourke remains popular in Texas, that’s not the case in Iowa.

A Civiqs/Iowa State U Poll this week gave O’Rourke 2% while a David Binder Research/Focus On Rural poll gave him 1%.

The most recent polls in New Hampshire, Nevada and South Carolina show O’Rourke at 1% to 3%.

SMU political science professor Cal Jillson says candidates who don’t finish in the top three in Iowa or the three other early states won’t make it very far.

“If you perform poorly in Iowa, New Hampshire, Nevada, and South Carolina, you’re going to be so much out of the fight, that you’re not going to do well in Texas. You have to put time in your home state to perform well. But if you’re beaten badly before you get to Texas, Texans are going to know that and they’re going to abandon you for people still in the race,” said Jillson.

In remarks following Sunday’s rally, O’Rourke said he is not considering an all-in strategy in Iowa.

He said while he has visited Iowa a lot, he has also visited 24 other states, including some the other candidates haven’t been to.

“I have a chance to bring those people their stories, their conversations into the story in Iowa, a state that’s going to help decide this race disproportionate to its size and the number of people involved. So this is a true nationwide campaign.”

O’Rourke campaigned in California and Colorado.

He will return to Iowa Saturday, then plans to visit Illinois, Indiana, Ohio and Pennsylvania.