Republicans have finally rolled out their plan for tax reform, and the reception has been a mixed bag.

The centerpieces of the GOP plan are a doubling of the federal standard deduction and a major cut to the corporate tax rate. But some Americans have expressed concern about other elements of the plan, such as lower caps on the mortgage interest and property tax deductions, the elimination of the estate tax and the student loan interest deduction, and the retention of the carried interest loophole.

Just how deep does the skepticism run? In an ABC News poll, 60 percent of Americans say the plan favors the wealthy, a figure that will burden President Donald Trump, Speaker Paul Ryan, and the rest of the Republican leadership with an uphill battle to pass legislation.

There is obviously a long way to go before this plan becomes a reality, and it will likely go through various incarnations before it gets to the House floor. But that hasn't stopped many small-business owners from wondering how they'll be affected should this proposal be written into law.

At first blush, the benefits for small businesses aren't very abundant. While the new plan would cut the statutory corporate tax rate from 35 percent to 20 percent, and allow multinationals to repatriate foreign income on "high-profit returns" (such as intellectual property) back into the U.S. at a rate of just 10 percent (12 percent on cash held offshore and 5 percent for non-cash assets), those changes won't impact most small businesses.

The IRS reports that for tax year 2013, the most recent year for which comprehensive data is available, there were 5.9 million active corporations paying taxes. Of those, 4.3 million (72 percent) are structured as pass-through entities, such as S-corporations and limited liability corporations (LLCs). These types of companies do not pay federal taxes at the corporate tax rate, but rather pass along profits and losses to their shareholders -- in many cases, the business owners themselves -- who are then taxed at the individual rate, which can be as high as 39.6 percent, under current tax law and in the Republican proposal.

Under the Republican tax plan, that pass-through rate falls to 25 percent. While that may seem like a windfall, many small business advocates -- including The National Federation of Independent Business -- say that's not the case. Critics argue a significant number of small businesses make less than $250,000, so they already pay less than 25 percent in taxes.

Moreover, there is a stipulation in the proposal which says the 25 percent pass-through rate applies only to passive owners of these businesses. For those who are directly involved in the daily operation of the business -- say, the owner/operator of a small trucking business, or the proprietor of a professional services firm -- the bill presumes that 70 percent of that pass-through income is attributable to labor and makes it taxable at the higher individual income tax rate. There is a second test under the legislation that establishes a ratio of wage income and business income based on level of capital investment that some industries, such as doctors, accountants, lawyers, are required to use this second test.

It begs the question: Who does win big? The answer: Large, multinational corporations.

The big cut to the headline corporate tax rate and the repatriation tax relief have been pillars of President Trump's platform since long before he was elected. As he readied to take office back in January, I wrote about the his plans for corporate taxes, and it reads very similar to what is being presented: cut the corporate tax rate to 15 percent with a repatriation period on overseas earnings taxed at 10 percent.

But critics of this plan have been warning for years that a repatriation tax holiday could produce very mixed results, as it has in the past when the U.S. implemented a similar plan in 2004. And with most corporations effectively paying far below the statutory rate as it is, some doubt exists as to whether these efforts will have as big an impact as one might hope. A new study just released by WalletHub, for example, finds the average corporate tax rate paid by companies in the S&P 100 is roughly 27 percent.

As tax reform evolves, and Congress lines up to make sure their respective constituents' concerns are accounted for, we may see some tweaking around the edges. But it seems the primary focus of this plan is not American small business, and one wonders whether that will present a significant roadblock in getting the legislation passed.