GOP Trump critics moving closer to launching 2020 primary challenges

Two former GOP congressmen critical of President Donald Trump's conduct in office and ballooning federal spending are moving closer to mounting long-shot primary bids against the president, moves that could weaken Trump ahead of the 2020 general election.

Former Illinois congressman-turned-radio host Joe Walsh is expected to launch a long shot primary challenge against President Trump for the Republican Party nomination, with an announcement that could come as early as this weekend, a senior advisor to Walsh tells ABC News.

Walsh’s team says the former one-term Tea Party Republican with a long history of incendiary comments - once a fervent Trump supporter who recently distanced himself from the president, accusing Trump of inflaming racial tensions - is looking to travel to and spend “a lot of time” in the key primary states of Iowa and New Hampshire in the coming weeks.

Both the latest events stemming from the Trump administration this week and what Walsh’s team calls an “incredible reaction” and flood of support following his op-Ed in the New York Times last week, ultimately pushed the conservative radio host further along than ever toward jumping in and challenging the President.

On Wednesday, former South Carolina governor and congressman Mark Sanford told ABC News he is inching closer to entering the race after meeting with party activists in New Hampshire last week.

"I continue to gravitate in that direction based on green lights as opposed to red lights," he said of the reception he received in the Granite State.

Sanford said he found "fertile ground" for a campaign focused on fiscal issues. "Republicans have lost their way on debt, deficit and spending," he said. "People in the Granite State have a degree of financial prudence baked into their DNA that fits into some of the themes I’ve long cared about."

The South Carolina Republican said he's still on track to make a decision about a running for president by Labor Day. He said the "overwhelming" and "gargantuan" challenges associated with mounting a White House bid "would frighten anyone that's thinking clearly," and are still on his mind.

Neither Walsh nor Sanford think they have a chance of wrestling the GOP nomination from Trump, but instead hope to offer GOP voters an alternative vision for the party while perhaps weakening the incumbent president along the way. Sanford in particular pointed to former Presidents Jimmy Carter and George H. W. Bush who were both roughed up by serious primary challenges on their way to losing their respective reelection races.

To Sanford, Trump has continued to demonstrate unfitness for office with recent comments this week accusing American Jews of disloyalty if they vote for Democrats.

"In his world it is personal allegiance that matters," he said. "Ultimately I think it is another corrosive element to the Trump presidency and the way it operates."