Sen. Ron Johnson, R-Wis., hopes that his federal lawsuit to eliminate an Obamacare subsidy for congressional employees will motivate lawmakers to change the law and that it will teach President Obama that he can't revise the health care legislation unilaterally.

Congressmen need to feel the same "harsh reality" of Obamacare as all other Americans, he said. "The next wave of lost policies is going to be those individuals getting their health care coverage through their employers," Johnson explained during a Monday press briefing.

"When they lose their coverage, now they're going to have to obtain it through an exchange — exactly what members of Congress and their staff are having to do. Here's the difference and here's the special treatment: Only members of Congress and their staff, when they lose their employer-sponsored care, will be able to have their employers make a tax-advantaged contribution to their health care plan. That's the special treatment. That's completely unfair, completely unjust."

Johnson enlisted conservative power lawyer Paul Clement, who argued the major challenge to the constitutionality of the individual mandate in 2012, to make the case against the regulation promulgated by the Office of Personnel Management.

"Congress specifically considered the question of whether or not members of Congress should get their health care in the same way as their constituents," Clement said during the briefing. "The OPM rule, and this is the heart of the challenge that's been filed today, really interferes with that congressional judgement. It stops what happened in the halls of Congress and effectively relaxes the impact of the decision that Congress made to make Congress and its staff members directly deal with the exact same health care situation as their constituents."

The lawsuit was filed in the Eastern District of Wisconsin by the Wisconsin Institute for Law and Liberty, on Johnson's behalf.

"Taxpayers who are aggrieved by government action should be able to hail their government into court where they reside," WILL president Rick Esenberg said to explain why the group didn't file the lawsuit in Washington. "It is in Wisconsin where his constituents — many of whom have lost their health care coverage and who are not able to get these tax-free premium subsidies from their employers — are feeling that pain, and, we thought it was appropriate for us to file that lawsuit in his home state."

Johnson said he hopes the lawsuit, if successful, will serve as a reminder that presidents cannot use their constitutional discretion in implementing the laws as an excuse to make unilateral changes to the law.

"I'm being critical of a president who knows no legal bounds," he said, referring to Obama's decision to delay the employer mandate, in addition to the OPM rule.

The Senate Ethics Committee informed Johnson that he can pay for the lawsuit on his own or raise money through his Senate campaign committee to finance the legal challenge.

"I'm hoping to be able to, quite honestly, raise funds through my campaign committee," he told reporters. "An awful lot of members wouldn't do that. You've got campaign finance [law] that limits contributions — when you're running for re-election, those can be some pretty precious dollars. I think this is such an important issue that I'm more than willing to either fund it personally or utilize those limited campaign funds. So, that's how it's going to be funded."

Johnson will be defending his seat in the blue state of Wisconsin during the 2016 presidential cycle.