“I’m not sure she’d freeze the field,” said Doug Hattaway, a senior strategist on Clinton’s 2008 presidential campaign. “We’ll wait to see what she does, but others will get started cultivating donors, staffers, and grassroots supporters. That would be a smart strategy, if you think you’ve got a shot at this, to put pressure on the perceived front-runner.”

Paul Begala — an early backer of Clinton’s 2008 campaign 16 years after he and Carville helped steered her husband into the White House — also suggested that Clinton might not have quite as long to make up her mind as is widely perceived.

“Hillary may be able to freeze the field, but Democratic activists are going to turn the heat up on her,” he said…

“She could mobilize support quicker than most, but presidential cycles are starting earlier and earlier, and you need a good 18 months to gear it all up, even as a front-runner,” Hattaway said. “A candidate with her following and stature can gear that infrastructure up more quickly than others, but not overnight.”